A Historical Overview of the Status of Function Words in Dependency Grammar

A Historical Overview of the Status of Function Words in Dependency Grammar Timothy Osborne Daniel Maxwell Zhejiang University US Chess Center Hangzhou Washington DC China USA [email protected] [email protected] (1) eaten Abstract kids have school This contribution provides a historical The at overview of the analysis of function words in a. The kids have eaten at school. surface syntactic dependency hierarchies. Starting with Tesnière (1959), the overview The USD analysis shown with (1a) stands in progresses through some prominent voices in contrast to more conventional analyses, which the history of DG (Mel'čuk 1958, 1963, Hays position auxiliaries as heads over content verbs 1964, Matthews 1981, Schubert 1987, and prepositions as heads over their nouns: Maxwell and Schubert 1989, Hudson 1976, 1984, etc.). The overview establishes that the (1) have analysis of prepositions has been almost kids eaten unanimous: they are positioned as heads over The at their nouns. There has been more variation concerning the status of auxiliary verbs, school although most DG grammarians have viewed them as heads over their content verbs. b. The kids have eaten at school. Concerning determiners, the dominant position In pursuing the analysis in (1a), USD is advocat- is that they are dependents under their nouns, ing an understanding of surface dependencies although there are a couple of prominent that is generally contrary to the views about voices that assume the opposite stance. function words that have crystallized over the decades in support of the analysis in (1b). 1 The dependency status of function This contribution surveys some prominent words voices in the DG tradition, in order to determine the extent to which the analysis in (1a) has been The distinction between function words and con- advocated over the decades since Tesnière (1959) tent words has been made by linguists of various and the period in which computational linguistics backgrounds. A rough definition of the distinction has become influential. Space does not allow us might be that content words can be understood to try to evaluate these analyses in detail, but without any supporting context whereas function when the authors of these analyses attempt to words cannot. The discussion in this article takes justify their decisions, we occasionally make place in terms of specific syntactic categories comments about their argumentation. which happen to be function words according to this definition. 2 Tesnière (1959/2015) A recent proposal for surface analyses of dependencies categorically subordinates function Tesnière’s analysis of function words has not words to content words. Universal Stanford De- survived into most modern DGs. The reason it pendencies (USD) (de Marneffe et al. 2014) ad- has not done so is tied to the fact that Tesnière’s vocate an annotation scheme that positions aux- subtheory of transfer has also not survived into iliary verbs, adpositions, subordinators, and de- most modern DGs. Tesnière viewed most func- terminers as dependents of the content words with tion words as translatives (auxiliary verbs, pre- which they co-occur. Thus according to this positions, subordinators, many determiners). As scheme, the DG analysis of the sentence The kids such, they were not granted autonomy in the have eaten at school would be as follows: syntactic representations, but rather they ap- peared together with a content word, the two 241 Proceedings of the Third International Conference on Dependency Linguistics (Depling 2015), pages 241–250, Uppsala, Sweden, August 24–26 2015. forming a dissociated nucleus. What this means Each of the top bubbles encloses the words of a in the current context is that Tesniere’s Éléments single nucleus. Neither word in a bubble is head (1959) did not provide much direct guidance over the other. concerning the dependency analysis of function This greater point established, one can never- words. theless examine Tesnière’s analysis of disso- While Tesnière is widely credited as the father ciated nuclei more closely. When one does so, of modern DGs, he himself was not aware of the one sees that he actually did provide some indi- dependency vs. constituency distinction. That rect guidance concerning the dependency analy- distinction was first established a few years after sis of function words. He drew a distinction be- his death. Hays (1964) is generally credited with tween the structural and the semantic function of establishing the term dependency grammar (as a nucleus (Chapter 29). In a disassociated nuc- opposed to phrase structure grammar). Thus the leus, one of the words guarantees the structural fact that Tesnière’s account of function words left integrity of the nucleus, and the other its seman- much room for debate about the actual depen- tic integrity. He also comments (Chapter 29, §18) dency status of function words should not be so that from an etymological point of view, the sub- surprising. Tesnière never intended to produce an sidiary word in a dissociated nucleus was once account of function words that would be consis- dependent on the constitutive word. tent with the purely dependency-based theories Tesnière later (Chapter 38, §19) states that of syntax that followed him. auxiliary verbs, despite the fact that they lack The relevant aspect of Tesnière’s grammar semantic content, are constitutive of the nucleus can be seen with the sentence Bernard est frappé in which they appear. Thus given these state- par Alfred ‘Bernard is hit by Alfred’, the struc- ments, one can extrapolate that, had Tesnière ture of which Tesnière showed with his Stemma been forced to choose, he would have viewed the 95: auxiliary verb as head over the content verb. Us- ing his conventions, he might have produced an (2) est frappé analysis of the sentence Alfred est grand ‘Alfred Bernard par Alfred is big’ along the following lines: The noteworthy aspect of this stemma is the (4) .est manner in which est frappé and par Alfred together occupy a single node each time. Neither grand can the function word be viewed as head/parent over the content word nor can the content word .Alfred be viewed as head over the function word.1 For The two words est and grand together still form a Tesnière, the two words est and frappé, and the single nucleus, but now the auxiliary verb is two words par and Alfred, formed a single nuc- shown as head over the adjective, and at the leus together each time. same time, the two together form a single head When Tesnière wanted to draw attention to over the noun Alfred. the fact that a given function word forms a nuc- One can also extend this extrapolated analysis leus together with a content word, he put the two to prepositions. Tesnière viewed a preposition as in a bubble. His stemmas of the sentences Alfred subsidiary to the noun with which it forms a dis- est arrivé ‘Alfred has arrived’ (Stemma 27) and sociated nucleus (Chapter 29, §4). Thus for the Alfred est grand ‘Alfred is big’ (Stemma 28) are phrase livre d’Alfred, lit. ‘book of Alfred’, the given here: following analysis reflects the distinction be- 2 tween constitutive and subsidiary words inside (3) est arrivé est grand the nucleus: a. Alfred b. Alfred (5) livre Alfred 1 One of us coauthors prefers the term parent to head ..d’ in this context, reserving the latter term for one specific kind of parent, namely those which are content In other words, Tesnière would probably have words rather than function words. 2The use of est ‘is’ in what is often considered two preferred an analysis that views prepositions as different ways is taken up in section 3.2. dependents of their nouns, if forced to choose. 242 Concerning the other two relevant types of formalization of dependency-based rewrite rules, function words, i.e. subordinators and articles, as inspired directly by Chomsky (1957), and on Tesnière viewed subordinators as translatives the extent to which dependency and constituency that were essentially the same as prepositions in formalisms are weakly or strongly equivalent. how they function. Translatives are part of Tes- One can merely glean a sense of Hays’ under- nière’s theory of transfer, developed in the standing of function words from the article. second half of his book. The purpose of a trans- In particular, Hays discusses the ambiguous lative is to transfer a content word of one cate- sentence They are flying planes, and he captures gory to a content word of another category, e.g. a the ambiguity with the following trees: noun to an adjective, an adjective to an adverb, a (6) o verb to noun, etc. Thus he probably would have favored subordinating them to the verb with o o o which they co-occur inside the nucleus. And a. They are flying planes. concerning articles (definite and indefinite), he o took a varied stance, viewing them as translatives . .o o when they perform a translative function, but as mere dependents of their noun when they do not o perform a translative function. b. They are flying planes. 3 Some early works Tree (6a) reflects the meaning ‘They are making the planes fly’, whereas tree (6b) reflects the 3.1 Mel'čuk (1958, 1963, 1974, etc.) meaning ‘They are planes that are flying’. Hays does not discuss the varying status of the aux- Unlike Tesnière, Igor Mel'čuk has been clear and iliary/copula are in these cases. But from the consistent about the dependency status of func- trees the reader can see that are is taken to be an tion words in surface syntax. Mel'čuk and his auxiliary verb in tree (6a) and a copular verb in collaborators have consistently subordinated tree (6b).

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